North Bondi Urban Cliff, NSW

The first time Brendan Moran saw his north Bondi block, it was so steep and inaccessible he didn't bother getting out of the car. But wife Penny was undeterred. She saw the potential in the awkward L-shaped, battle-axe block. Despite being hemmed in on all sides by surrounding houses and with just one skinny laneway in, they reckoned they could squeeze all they needed for them and their four kids on this block by simply going up. 

Four levels should do it, rising 14m in the air with an infinity edge pool, and they're pushing building regulations to get it all in. But excavating this ex-quarry is more complicated than they think. In fact, every stage of the build is hampered by the challenges of the block. It's so tight there's nowhere for the tradies to put anything, and keeping peace with the neighbours is a full-time job. 

With builder and mentor Martin at the helm, Penny dons the work boots and hard hat, and gets on the tools. Her passion is building and she's all over the intricacies of the build as she juggles her life as a tradie with being a mum. After a family holiday to Thailand, she and Brendan return refreshed and inspired to make substantial structural changes they say will make their house even better. From changing the entire entrance to lifting ceiling heights and redesigning the pool to make it even longer and deeper, the complexity of this construction would challenge even the most seasoned builders. 

After numerous council applications and changes that blow their bank balance, and schedule, right out of the water, their spontaneous decision-making threatens to spiral out of control. As costs soar into the millions, there's no guarantee how or when this multi-tiered tower will ever get done.